The present embodiments relate to ink compositions suitable for printing marks or images on deformable substrates. In particular, disclosed herein is a stretchable ink composition. These ink compositions can be used for ink jet printing.
Printing marks or images on deformable substrates is desirable for many applications, such as flexible medical devices, including surgical tools and implantable medical devices, robot skins, textiles (e.g., for stretchable swimming suits), rubber products such as tires, tubes, and cables, and the like. Consumable products based on rubbers and some textiles are also stretchable. Because of the highly deformable characteristic of the substrate, a stretchable ink is desired for printing on such substrates to achieve excellent image quality, image robustness, and image longevity.
Accordingly, while known compositions and processes are suitable for their intended purposes, a need remains for improved ink compositions with certain characteristics. Specifically, a need remains for ink compositions suitable for printing on deformable or stretchable substrates. Additionally, a need remains for stretchable inks that form robust images which can be stretched and relaxed for a high number of cycles. There is also a need for stretchable inks that have good color stability. There is also a need for stretchable inks that exhibit good resistance to environmental factors such as light, chemicals, water, and oxidizing gases, thus generating hydrophobic and water-resistance images. Ideally, the stretchable ink would be suitable for both indoor and outdoor applications. Lastly, it would be desirable that such inks can be applied digitally.
Previous work by the inventors included a stretchable ink composition which comprises water, a colorant, a surfactant, and a fluoroelastomer, as disclosed in U.S. patent application Ser. No. 13/182,579 to Wu et al., filed on Jul. 14, 2011, and an aqueous-based latex approach for elastic ink, as disclosed in U.S. patent application Ser. No. 13/495,915 to Wu et al., filed on Jun. 13, 2012, which are hereby incorporated by reference in their entireties. In contrast to the prior approaches, the present embodiments are based on a solventless approach. As such, there is no need to dry off residual water, which saves time and energy. In addition, there is no vapors from any organic solvents, so this approach is environmentally friendly.